Wilson's "Under Our Skin," which screens Friday at San Francisco's Sundance Kabuki Cinema, has managed to transform the unlikely topic of a bacterial infection into a critical hit on the festival circuit.

The film is also credited with reigniting a discussion about the merits of Lyme, an ailment that's been largely misunderstood - or flat out denied - by the medical establishment. In the United States, the Centers for Disease Control and Prevention reported 35,000 new cases of Lyme disease last year, a 71 percent increase over the past two years, which means new Lyme cases are almost as prevalent as new HIV cases (39,000). Because Lyme tests are inaccurate and cases go unreported, one CDC estimate put the true number of current cases at 300,000.

"If this were HIV or West Nile virus," Wilson said, "we'd be doing everything we could."

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Wilson's first contact with Lyme began as a child when his twin sister was diagnosed. "All I knew about it was that she was achy, tired all the time, and complaining."

But it became a topic of serious interest about five years ago when a friend in Marin who'd originally been diagnosed with Lou Gehrig's disease - "a death sentence," Wilson said - turned out to be suffering from an untreated case of chronic Lyme.

As Wilson learned, patients are often misdiagnosed with maladies ranging from chronic fatigue syndrome to multiple sclerosis to Lou Gehrig's. Making the disease more difficult to identify, as many as 50 percent of all Lyme tests are inaccurate, and patients are often told their case is psychosomatic. Because there's no cure (antibiotics are an early treatment), many sufferers are left to treat their symptoms with no hope of solving the disease.

"I uncovered a whole world of untold suffering," Wilson said. "And what seemed to me like a medical fraud."

Lyme is a bacterial infection, a vector-borne disease passed along to humans through a deer tick. It's been commonly believed that the ticks live only on the East Coast, but Lyme cases have been reported in all states and all continents except Antarctica, according to the CDC.

Early symptoms include fever, headaches and fatigue, making it difficult to detect in the critical early stages. One of the questions that nagged at Wilson during filming was trying to understand why the big pharmaceutical companies weren't working diligently for a cure. After all, with plenty of patients and potential customers, profits would be a boon.

Wilson came to a multipronged conclusion. First, because Lyme is not easily defined and diagnosed, it's difficult to find a singular cure. Second, the best treatment can be antibiotics, which generate little profit for the big pharmaceuticals.

"But there is a lot of money in keeping people chronically ill," Wilson said, noting that steroids, painkillers and a slew of drugs can treat the symptoms of Lyme.

"I think we're moving away from magic bullet era and into understanding illness as combination of factors," he said. "That's one reason the disease is difficult to grasp - it challenges our current understanding of medicine."

So far, Wilson's film has been viewed by health organizations and doctors who are reconsidering the threat of Lyme. He also receives e-mails from patients who've found hope in the subjects he profiled.

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"I get comments saying, 'Your film saved my life,' " Wilson said. "And really, what better reward can you have than that?"

Ailment largely misunderstood

In 2008, there were 35,000 new reported cases of the disease, according to the Centers for Disease Control. The CDC acknowledged that the actual number of cases in the United States could exceed 300,000 because of flaws in testing and reporting.

Lyme cases have been reported in every U.S. state and on every continent except Antarctica.

Only 35 to 59 percent of Lyme patients reported the red circular bull's-eye rash after the tick bite that confirms infection.

Lyme is commonly misdiagnosed as chronic fatigue syndrome, fibromyalgia, lupus and multiple sclerosis, among other ailments.

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